I'm basically having this problem:

http://support.microsoft.com/kb/920875

except that the page has a hotfix for only XP and not Vista! Hmmm....




"A L" wrote:

Hello-

All of a sudden a few days ago, many of my USB devices started showing as
Unknown Devices in the Device Manager. I've read that this sometimes happens
in WinXP too- but no post that I found about the problem proposed a solution
(for Vista or XP.) If I disable the "Standard Enhanced PC to USB Host
Controller", the system then locates drivers for all of the devices, but runs
them in USB 1.1 (slow!) mode.

I'm seeing this for flash storage devices (thumb drives, flash card readers,
ipod), logitech quickcam 5000, plantronics USB headset etc. Oddly, my MS
Intellimouse Explorer 3.0 and APC UPS work fine!

Anyone know what to do?
I have a ton of USB devices defined in the registry under
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Enum\USB\ , but regedit does not
allow me to remove any of these.

I also unfortunately don't have a System Restore Point to back when my USB
devices were working.

If anyone has ideas for something to try, please post! Thanks, Al